NEUROTOXIC EFFECTS OF DOXYCYCLINE SCLEROTHERAPY

A patient experienced phrenic nerve paralysis after doxycycline sclero therapy for treatment of chylous fistula at our institution. The purpo se of this study is to use physiologic testing to determine whether do xycycline is capable of inducing defects in neural function, A nonrand omized, controlled trial was performed with nerve-conduction studies t o determine possible deleterious effects of doxycycline sclerotherapy. Thirty-eight CD rats were used and separated into four groups, Doxycy cline was applied to the sciatic nerves of rats by either topical appl ication directly on the nerve or by intraneural injection, Nerve-condu ction studies were done before surgery and at 1, 7, and 21 days after surgery, The results showed a statistically significant decrement in n erve-conduction velocity and strength of transmitted impulse in those nerves injected with doxycycline solution, Complete nerve block was se en frequently, This effect was not seen with topical application of do xycycline or normal saline solution or with intraneural injection of n ormal saline solution, This study demonstrates that doxycycline can in duce a marked decrement in neural function when applied to the subepin eural layers of the sciatic nerve in the rat. Therefore doxycycline sc lerotherapy should be used with great caution in situations in which i t could become exposed to nerves that have sustained surgical trauma.